Use late-bound entity class with a LINQ query
Applies To: Dynamics 365 (online), Dynamics 365 (on-premises), Dynamics CRM 2016, Dynamics CRM Online
In Microsoft Dynamics 365 and Microsoft Dynamics 365 (online), you can use late binding with .NET Language-Integrated Query (LINQ) queries. Late binding uses the attribute logical name, and is resolved at runtime.
In This Topic
Using late binding in a join clause
Using late binding in a left join
Using late binding and the Contains method
Using late binding and not equals operator
Using the GetAttributeValue method
Using late binding in a join clause
The following examples show how to use late binding in the join clause of a LINQ query.
Retrieve the full name of the contact that represents the primary contact for an account and the account name.
using (OrganizationServiceContext orgSvcContext = new OrganizationServiceContext(_serviceProxy))
{
var query_join2 = from c in orgSvcContext.CreateQuery("contact")
join a in orgSvcContext.CreateQuery("account")
on c["contactid"] equals a["primarycontactid"]
select new
{
contact_name = c["fullname"],
account_name = a["name"]
};
foreach (var c in query_join2)
{
System.Console.WriteLine(c.contact_name + " " + c.account_name);
}
}
Using orgSvcContext As New OrganizationServiceContext(_serviceProxy)
Dim query_join2 = From c In orgSvcContext.CreateQuery("contact") _
Join a In orgSvcContext.CreateQuery("account") _
On c("contactid") Equals a("primarycontactid") _
Select New With {Key .contact_name = c("fullname"),
Key .account_name = a("name")}
For Each c In query_join2
Console.WriteLine(c.contact_name.ToString() & " " _
& c.account_name.ToString())
Next c
End Using
Retrieve Contact, Account and Lead data where the Lead was the originating Lead and the Contact’s last name is not “Parker”
using (OrganizationServiceContext orgSvcContext = new OrganizationServiceContext(_serviceProxy))
{
var query_dejoin = from c in orgSvcContext.CreateQuery("contact")
join a in orgSvcContext.CreateQuery("account")
on c["contactid"] equals a["primarycontactid"]
join l in orgSvcContext.CreateQuery("lead")
on a["originatingleadid"] equals l["leadid"]
where (string)c["lastname"] != "Parker"
select new { Contact = c, Account = a, Lead = l };
foreach (var c in query_dejoin)
{
System.Console.WriteLine(c.Account.Attributes["name"] + " " +
c.Contact.Attributes["fullname"] + " " + c.Lead.Attributes["leadid"]);
}
}
Using orgSvcContext As New OrganizationServiceContext(_serviceProxy)
Dim query_dejoin = From c In orgSvcContext.CreateQuery("contact") _
Join a In orgSvcContext.CreateQuery("account")
On c("contactid") Equals a("primarycontactid") _
Join l In orgSvcContext.CreateQuery("lead") _
On a("originatingleadid") Equals l("leadid") _
Select New With {Key .Contact = c,
Key .Account = a,
Key .Lead = l}
For Each c In query_dejoin
Console.WriteLine(c.Account.Attributes("name").ToString() _
& " " _
& c.Contact.Attributes("fullname").ToString() _
& " " _
& c.Lead.Attributes("leadid").ToString())
Next c
End Using
Using late binding in a left join
The following example shows how to retrieve a list of Contact and Account information using a left join. A left join is designed to return parents with and without children from two sources. There is a correlation between parent and child, but no child may actually exist.
using (OrganizationServiceContext orgSvcContext = new OrganizationServiceContext(_serviceProxy))
{
var query_join9 = from a in orgSvcContext.CreateQuery("account")
join c in orgSvcContext.CreateQuery("contact")
on a["primarycontactid"] equals c["contactid"] into gr
from c_joined in gr.DefaultIfEmpty()
select new
{
account_name = a.Attributes["name"]
};
foreach (var c in query_join9)
{
System.Console.WriteLine(c.account_name);
}
}
Using orgSvcContext As New OrganizationServiceContext(_serviceProxy)
Dim query_join9 = From a In orgSvcContext.CreateQuery("account") _
Group Join c In orgSvcContext.CreateQuery("contact") _
On a("primarycontactid") Equals c("contactid") Into gr = _
Group From c_joined In gr.DefaultIfEmpty() _
Select New With {Key .account_name = a.Attributes("name")}
For Each c In query_join9
Console.WriteLine(c.account_name)
Next c
End Using
Using late binding and the Contains method
The following example shows how to use late binding with the Contains method in a LINQ query.
using (OrganizationServiceContext orgSvcContext = new OrganizationServiceContext(_serviceProxy))
{
var query_contains3 = from c in orgSvcContext.CreateQuery("contact")
where ((string)c["description"]).Contains("Coho")
select new
{
firstname = c.Attributes["firstname"],
lastname = c.Attributes["lastname"]
};
foreach (var c in query_contains3)
{
System.Console.WriteLine(c.firstname + " " + c.lastname);
}
}
Using orgSvcContext As New OrganizationServiceContext(_serviceProxy)
Dim query_contains3 = From c In orgSvcContext.CreateQuery("contact") _
Where (CStr(c("description"))).Contains("Coho") _
Select New With
{Key .firstname = c.Attributes("firstname"),
Key .lastname = c.Attributes("lastname")}
For Each c In query_contains3
Console.WriteLine(c.firstname.ToString() & " " _
& c.lastname.ToString())
Next c
End Using
Using late binding and not equals operator
The following example shows use of the not equals operator.
using (OrganizationServiceContext orgSvcContext = new OrganizationServiceContext(_serviceProxy))
{
var query_ne3 = from c in orgSvcContext.CreateQuery("contact")
where !c["address1_city"].Equals(null)
select new
{
FirstName = c["firstname"],
LastName = c["lastname"],
Address1_City = c["address1_city"]
};
foreach (var c in query_ne3)
{
System.Console.WriteLine(c.FirstName + " " +
c.LastName + " " + c.Address1_City);
}
}
Using orgSvcContext As New OrganizationServiceContext(_serviceProxy)
Dim query_ne3 = From c In orgSvcContext.CreateQuery("contact") _
Where (Not c("address1_city").Equals(Nothing)) _
Select New With {Key .FirstName = c("firstname"),
Key .LastName = c("lastname"),
Key .Address1_City =
c("address1_city")}
For Each c In query_ne3
Console.WriteLine(c.FirstName.ToString() & " " _
& c.LastName.ToString() & " " _
& c.Address1_City.ToString())
Next c
End Using
Using the GetAttributeValue method
The following example shows how to retrieve Contact information using the GetAttributeValue method.
using (OrganizationServiceContext orgSvcContext = new OrganizationServiceContext(_serviceProxy))
{
var list_getattrib1 = (from c in orgSvcContext.CreateQuery("contact")
where c.GetAttributeValue<Guid?>("contactid") != _contactId1
select new {
FirstName = c.GetAttributeValue<string>("firstname"),
LastName = c.GetAttributeValue<string>("lastname")
}).ToList();
foreach (var c in list_getattrib1)
{
System.Console.WriteLine(c.FirstName + " " + c.LastName);
}
}
Using orgSvcContext As New OrganizationServiceContext(_serviceProxy)
Dim list_getattrib1 = ( _
From c In orgSvcContext.CreateQuery("contact") _
Where Not c.GetAttributeValue(Of Guid?)("contactid") _
.Value.Equals(_contactId1) _
Select New With
{
Key .FirstName = c.GetAttributeValue(Of String)("firstname"),
Key .LastName = c.GetAttributeValue(Of String)("lastname")}
).ToList()
For Each c In list_getattrib1
Console.WriteLine(c.FirstName & " " & c.LastName)
Next c
End Using
See Also
CreateQuery<TEntity>
Build queries with LINQ (.NET language-integrated query)
Order results using entity attributes with LINQ
Microsoft Dynamics 365
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